Apparatus, methods, and computer programs

An apparatus of a service consumer, the apparatus comprising:

• at least one processor;
• and
• at least one memory comprising computer code that, when executed by the at least one processor, causes the apparatus to perform:
• signalling, to a network function, event subscription information comprising an intra-domain address and an inter-domain address for signalling event subscription notification information from a service producer to the service consumer;
• and
• receiving, at least one of:
• an event subscription notification addressed from a first service producer in the same domain as the apparatus to the intra-domain address, or
• an event subscription notification addressed from a second service producer in a different domain than the apparatus to the inter-domain address.

An apparatus of a first service producer, the apparatus comprising:

• at least one processor;
• and
• at least one memory comprising computer code that, when executed by the at least one processor, causes the apparatus to perform:
• receiving, from a network function, event subscription information comprising an intra-domain address and an inter-domain address for addressing event subscription notification information to a service consumer;
• selecting an address from the intra-domain address and the inter-domain address for addressing notification information to the service consumer,
• wherein the intra-domain address is selected when the first service producer is located in the same domain as the service consumer, and
• wherein the inter-domain address is selected when the first service producer is located in a different domain to the service consumer;
• and
• signalling notification information to the service consumer using the selected address.